This invention relates in general to a respirator device particularly for use in association with a person's trachea into which a tube is inserted and which includes means for supplying ventilating gas in a jet stream through the tube and for connecting the opposite end of the tube to the atmosphere and providing a controlled vacuum therein.
The invention concerns a respirator with a ventilating gas source controlled over a control device which feeds at least one jet nozzle arranged in the range of the distal end of a tracheal tube and within the inspiration phase with gas high-pressure pulses, whose sequential frequency is above the natural ventilation frequency, particularly above 300/min. and which includes a control device which switches at the end of the inspiration phase to the expiration phase and where a given pressure value deviating from the ambient atmosphere can be set at the proximal end of the tracheal tube.
An alternating positive-negative pressure ventilation (APV) can be effected with various known respirators. Depending on the selection of the positive and negative ventilation pressures and of the phase time ratio, the mean ventilation pressure can be kept in the positive or negative range or on the zero line.
An apparatus for alternating pressure ventilation is described in German patent No. 916,727. By means of an injector fed with ventilating gas, the air is exhausted from the lungs until a corresponding vacuum has been attained. This vacuum effects the switching of the injector action over control valves in such a way that the gas now arriving from the injector is forced into the lungs until a certain pressure value has been attained. The switching between the respiration phase is effected by means of a diaphragm controlled valve whose motion drive is based on the pressure difference between a space in communication with the lungs and the ambient atmosphere.
From German patent application No. P 29 47 659.3 is known a respirator with a ventilating gas source controlled by patient values over a control device, which can be operated with a tracheal tube or an insufflation catheter with jet nozzle, where the ventilating gas source generates in HFJV-operation (high-frequency jet ventilation) gas high-pressure pulses which form respiration pulse series and leave between these respiration pulse series intervals for expiration. A closing element permits the setting of a given pressure value deviating from the ambient atmosphere at the proximal end of the tracheal tube.